Trade negotiators from leading developed and developing nations spent three hours behind closed doors yesterday, seeking to break the logjam in global talks amid growing fears the six days of negotiations in Hong Kong were heading for failure.

After a second day of stalemate, the director-general of the World Trade Organisation, Pascal Lamy, warned ministers that time was running out for a deal that would allow the round of trade liberalisation talks launched in Doha four years ago to be completed by the end of next year.

Fresh protests outside the conference centre were mirrored by rows between negotiators over a package of help for poor countries and over cotton subsidies and agricultural and industrial tariffs.

Peter Mandelson, Europe's trade commissioner, said he was worried that the EU's proposal for the poorest countries to gain duty-free and quota-free access for their goods to rich western markets was being blocked. The US has raised objections to Bangladesh and Cambodia being included in the list of countries granted special treatment, and is opposed to textiles being included in the list of products. Japan has problems with allowing imported rice to compete with its heavily-protected domestic crop.

"I don't believe we should give up on this issue or allow the commitment to be diluted. If we can't deliver on this, the whole world will be asking what we are doing in Hong Kong," Mr Mandelson said.

Mr Mandelson said what was needed was "sensible, direct and reasonable-minded negotiations" of the sort ministers had when they met one-on-one. "Instead of negotiating proposals you get positions and statements. That's not going to lead to any breakthrough," he said.

"The brinkmanship and bidding-up on behalf of the large-scale agricultural exporters is self-defeating. Unless there are negotiations taking place in all areas there won't be an agreement in any area."

The US deputy trade representative, Karan Bhatia, rejected Mr Mandelson's argument that a special package for poor countries was vital to success in the round. "The gains for developing countries are going to be obtained only once we can make a breakthrough on agriculture," she said.

The US said it had a number of issues with the duty-free and quota-free package but hoped they could be resolved by the end of the talks on Sunday.

While the EU is under pressure to give ground on agriculture, cotton-producing countries in west Africa made it clear they were seeking concessions from the US over the billions of dollars it spends protecting its cotton farmers. Samuel Amehou, Benin's WTO ambassador, said: "We will reiterate our call not to accept any consensus that doesn't take the legitimate interests of African farmers into account."

A spokesman for Mr Lamy said: "We can't take the approach that we might have months ahead. The time line is short, not just for Hong Kong but until the deadline at the end of 2006. There is much to do."

Outside the conference hall, demonstrators held a carnival-like rally in a nearby park and staged a candlelit vigil on the shopping street in Causeway Bay. The mood was more wary than it had been the previous day amid rumours that this week's talks might not be the complete washout that protesters had hoped for.

"For us any agreement is bad. The US and Europe are trying to show they are positive about development issues, but obviously their main objective is to gain an agreement on services and manufacturing. If that means sacrificing agriculture, they will do it," said Paul Nicholson, European coordinator for Via Campesina, the umbrella organisation for the more than 2,000 agricultural workers among the protesters.